| Author | Message | ||
| Curt H (67.226.233.90)
Rating: N/A |
OK, I've got the toilet set in and plumbed into the black water tank. Have the bathroom and kitchen sinks set and am in the process of running the drain pipes which is to include a vent pipe out the roof, right? Ok , where can I get a vent pipe "cover" for the roof that won't allow rain water to come back inside the coach? I drill right through the roof right? Oh yea, should the toilet have a vent pipe of its own or can I connect to the sink vent pipes? Thanks in advance for the help. Curt H. PD4106-045 | ||
| FAST FRED (67.75.106.234) Rating: N/A |
Any RV supply or parts place will have a slip on cap for a couple of bucks.OR get a big RV catalog. You can go fan$ier , but low branches eating a $2.00 piece of plastic doesn't bring tears yo your eyes. FAST FRED | ||
| Phil (204.89.170.126) Rating: N/A |
I just had some roof repairs done to my Monaco at the factory and they simply used a "tee" on top of teh vent pipe. It is much studier than the vent caps that were on it and they keep the rain out. | ||
| two dogs (66.90.217.98) Rating: N/A |
I did it different...came out of vent, went down 12", over two inches,up 12", another"U" & back through the floor of the cargo bay...the "first" "U" has about 4oz. of anti-freeze in it ...works great & no holes in my roof... | ||
| Jayjay (198.81.26.108) Rating: N/A |
A very common way to do a vent is take it out into the rear wheel well or engine compartment, instead of through the roof. It's not like a house where you are tied to a city sewer line...the only time there is air flow out of the vent is when you flush or run water in the sink. Many of the coaches at rallys are done this way, and you will never smell them. Oh, and it's not against the plumbinbg codes-yes, there has to be a vent (just one), but there is no spec on height above floor/ground/nose etc. As to your question about tying the sink/commode together...if they are close together that would work well ,but if it is inconvenient tnen use two vents. Cheers...JJ | ||
| R.C.Bishop (128.123.221.174)
Rating: N/A |
Do I read you guys right that the vent can exit below floor level and still not smell? Also, what's the purpose of the anti-freeze in the vent line? I'm confused,.... I think.  RCB '64 Crown Highway Coach | ||
| Jay Gerlick (67.250.219.33)
Rating: N/A |
I sent two vents thru the roof 1 for the fresh water and 1 for the black and grey ( those two are tied together in the wall) I didn't want to combine the vent from the toilet with the fresh water vent. Also went thru the roof down wind from the roof vent (5'). I've been by a wheel well vent, maybe he did something wrong installing it, but it stank !!!! ALL the time. I got my vents for $2.00 ea at one of the many surplus stores in Elkhart (can't remember which one) | ||
| two dogs (66.90.213.92) Rating: N/A |
I spent 1/2 day doing this...but I will do anything not to have holes in the roof...it's all out of 3/4 p.v.c.the first "U" has anti-freeze in it so there is no constant vent (NO SMELL)the second "U" is not glued on ,that's how you get the anti-freeze in (and check it)....when you flush the toilet,you add 1 gallon of stuff to your tank...you have to get rid of 1 gallon air from your tank...my contrabution to busnuts...we will call it the "TWO DOGS VENT"....use the minimum amount of anti-freeze,only enough to fill the little 2" "U" | ||
| Ross Carlisle (Ross) (66.238.216.74)
Rating: N/A |
The vent should allow the sewer gasses to freely escape upward. Methane gas is very flamable and if alowed to collect without venting, can cause an explosion hazard. By venting downward, you are not allowing the sewer gasses to vent freely as they build up. Venting downward will cause methane gas to accumulate in any portion of the system that is higher than the vent outlet. The gasses will vent as they build, but there would always be a concentration of gas in the system. Even worse, by plugging the vent with antifreeze, you are preventing the gasses to escape until liquid is added to the tanks displacing gas and forcing it past the antifreeze plug. This would allow an even higher concentration of methane to accumulate. Methane gas rises, so in a system that vents through the roof, the gasses are allowed to escape naturally as they accumulate, eliminating any danger of explosion. Your approach addresses one purpose for a vent which is to displace air when liquid is added, but it does not address the most important purpose of a vent, which is to vent explosive gas. This is why a vent in a house will not pass code if any portion of it runs downhill. | ||
| two dogs (66.90.217.117) Rating: N/A |
I knew they'd be somebody like you...always is | ||
| Ross Carlisle (Ross) (66.238.216.74)
Rating: N/A |
Code is code...I didn't write it. Dave Galey did a nice article in BCM about tank venting and why it is important to vent through the roof. I was mearly pointing out that venting a sewer tank down is not a safe way of doing it, but if it works for you, thats all that counts. Ross | ||
| Gary Stadler (Boogiethecat) (68.7.217.217)
Rating: N/A |
Whenever I stick a vent pipe thru the roof, I cut it at a 45 degree angle with the tall side facing forward. What this does for you is when you're driving down the road it acts like a bit of a venturi, putting a small vacuum on the system. Then when someone flushes the pottie while underway, air goes IN to the toilet instead of possibly coming out and stinking up the whole bus. It works really well and looks nice on the roof... Cheers Gary | ||
| Henry R. Bergman, Jr. (Henryofcj) (63.224.197.10)
Rating: N/A |
Kinda smells sticky to me. | ||
| R C Bishop (128.123.221.141)
Rating: N/A |
Thanx, Ross.........as I suspicioned. Something just....smelled....to me. RCB | ||
| Curt H (67.226.233.70)
Rating: N/A |
Thanks friends for all the suggestions. I think I'll try and install it this week-end. As always , this discussion list is perfect for us newbies.One of these days we'll get her on the road. Thanks again, Curt H PD4106-045 | ||
| Jim-Bob (64.12.96.235) Rating: N/A |
My bus came to me 3 years ago with a 1 1/2" vent from the top of the black/grey tank that goes down through the bay floor. We have lived with this for some time and about 20,000 miles. We have learned that: 1. There is a high pressure area under the bus when driving down the road. This produces a lot of pressure in the tank & when you flush the john, foul odor FILLS the bus, all the way up to the driver's seat!!! It also blew a face full of dry toilet deodorant chemical 3' up into my wife's face & eyes one day when she stepped on the pedal to add the chemical to the tank (cause it stank)! 2. The tank DOES collect methane since it is lighter than air. Even sitting still, when you flush, the bowl (opening) is higher than the vent so air is drawn in below the bus & PEW comes up from the bowl. 3. I have tried a rear facing 90 degree elbow at the bottom of the vent which helped a little when rolling. 4. When you are sitting outside the bus, it stinks if the breeze is coming from the other side of the bus... always! 5. Our fresh water tank vents at the top of the bay, about 6" above the tank, This has given no trouble except the time we overfilled the tank. This vent should vent to the outside, but screen it to keep bugs & wasps, etc out. In short, we have tried it and it DOES NOT WORK. The roof sewer vent is the only way to go. It is well worth the 1 1/2" or so hole. By the way, at the RV store, you can buy either a plastic vent or a galvanized one. Either one should be safe up there because the vent doesn't stick up near as far a roof air cond. or a fridge roof vent. I hope you can benefit from our experience. Jim-Bob | ||
| jmaxwell (66.42.92.25) Rating: N/A |
Just to add to Ross' astute observations, the Two Dogs 3/4" pipe is not adequate. And, code does not allow more than a 45 degree bend in a vent unless it terminates directly above the bend, so that sort of eliminates Two Dogs trap and inverted trap arrangement. Also available for long horizontal runs back to the tank are inside vents. They do not vent the system but they do aide in drainage of longer drain lines. They have a check built into the top of them that allows air into the line but not allow air(or gases) to vent out. | ||
| Jayjay (198.81.26.108) Rating: N/A |
With the regular drainage of a 50 to 100 gal. tank that most rigs have, I doubt very seriously if methane gas build up is going to be a problem . In my previous post I neglected to state that the vent line should be at least 1 1/2" and preferably 2" dia., and should rise constantly from tank to end. ...JJ | ||
| Jayjay (198.81.26.108) Rating: N/A |
As an addendum to my earlier post: I should have been more specific about using a 2" vent line and that it should have a positive rise from tank to end. Methane gas? From a 50 to 100 gal tank that gets treated and drained almost daily? I don't see how. ...JJ | ||
| FAST FRED (67.75.103.37) Rating: N/A |
JJ How do you go camping & use 100G pf water a day! Thats 2 WEEKS worth for many campers. Our coach sits , at times for 3 weeks between adventures , so the 2in roof vent is a great safty factor. Plumbing codes are not like RVIA codes. There to help keep YOU! alive , the RVIA is to "standardize" cheap/shoddy construction practices & garbage parts selection to keep a MFG alive. FAST FRED | ||
| Geoff (Geoff) (66.238.120.114)
Rating: N/A |
Here is a curve for everyone-- on my RTS I only have short vents that open 6" above the grey and and black tanks. This puts the openings right underneath the floor of the bus, but it is in a bay that is open to ventilation. Having the vent below the floor works for me to avoid overflow of the tanks into the bus-- especially since I have a house toilet. And while the house toilet uses a lot of water, the extra water keeps the smell down in the black tank so the short vent is not a problem. And I have no pipe coming inside the bus to deal with along with the hole in the roof. --Geoff '82 RTS CA | ||
| Don KS/TX (65.150.144.21)
Rating: N/A |
I disagree Jim Bob, the roof vent is not the ONLY way to go, in fact it is easy to hit a high pressure area up there too. I did not feel the desire for cutting some holes in the roof either, and ran my vent from combined grey/black tank up and back into the wheel well, as some others had done with great success. I NEVER had a smell or back pressure problem, and lived for months in an RV park with others close by, dumping once a week or so. My backup plan was to tee off into the engine intake area in case I had hit a high pressure area, it was never necessary. A proper chemical keeps the smell away regardless. | ||
| jmaxwell (66.42.92.18) Rating: N/A |
The simple idea of the vent is to get odors up, up, and away. I don't think methane gas is of nearly the concern that occurs in large municipal sewer systems or home systems (septics), even though it is present in smaller quantities in our conversions. The sewer vent concept is being applied to generator exhaust systems much the same way now. A low lying vent will exhaust odors below or at living area height, and that is not desirable. I have a washer standpipe that is trapped and when we have not used the washer for some time or the water trap in it sloshes out or evaporates, the odors are obnoxious in the bus. I plumbed a 1/4" water line into it to re-fill the trap and prevent the venting of odors into the bus. So, whatever works I suppose is fine, but it is necessary to get those odors above the nose line if you don't want to be uncomfortable. | ||
| Gary Stadler (Boogiethecat) (68.7.217.217)
Rating: N/A |
Just another thought about the roof hole that has worked really well for me... to seal it, I made the hole very close in size to the 1-1/2" pipe. Then I bought one of those rubber couplings, the kind that's basically a piece of rubber tubing (I think it's actually butyl) with two hose clamps. I sawed it in half, at an angle that matched the bus roof's curve, and installed one half inside, and the other half outside with some silicone inbetween and under each, but no hose clamp on the outside. It looks clean, there's not a chance it'll leak, and I'm very happy with it's outcome. Here's a photo http://www.heartmagic.com/00ventstuff.jpg Also there is my vent scheme that some will disagree with... I "wet-vented" my bathroom sink by sharing the same line for it's vent and drain... it works very well for me. I use a live bacteria treatment (the wet version if "Eco-Save" www.eco-save.com ) in my tanks and can leave them full for weeks on end, and never smell a thing ever... Cheers Gary | ||
| bobadame (129.82.229.195) Rating: N/A |
Methane gas, hmmm, how about venting into the air cleaner of the engine? Bob | ||
| Hal StClair (Hal) (65.160.214.159)
Rating: N/A |
One of the main reasons to vent the tanks above the roof is a sanitation issue,ie. smell,germs, etc. The size of the vent can be regulated by the type and number of fixtures in the system but the IPC (International Plumping Code) does not require a 2" vent on a WC (water closet) as the UPC did ( witch was oversized to prevent freezing closed the vent in cold, wet areas). The main concern we have in our conversions is with draining our holding tanks. There is a real possibility of collapsing the tanks or sucking the water out of the traps which results in some really foul smells. Connecting fresh and waste tanks together with vents is strictly forbidden (known as a cross connection). Although black and gray tanks must be vented through the roof, there is no reason to do the same with fresh water tanks.They do need a vent, but going through the roof isn't required. Everyone to their own, but the rules are in black and white. Ya makes your own choices, good luck. Hal | ||
| DaveD (64.235.198.76)
Rating: N/A |
Just a point of clairifcation, the ANSI RV standards in the USA and CSA standards in Canada, used by RVIA (USA)and CRVA (Canada)follow much of the same requirements as residential codes. Where applicable, they make reference to the residential standards. They are generally not a relaxation of residential codes and include some vital potentially life-saving requirements. For my grey water and black water tanks I installed separate vents for each and capped these with standard low cost plastic RV vent flanges and caps. I also used two grommets designed to be used with waste water tanks, around each vent pipe, giving an excellent tight seal between the outside of each pipe and the holes in the roof. The RV vent cap flanges also provide a seal for the roof openings and I applied sealant between these and the roof surface. Dave Dulmage (MC-8) | ||
| Jayjay (198.81.26.108) Rating: N/A |
Hey FF, where you been lately? Nice to see you back. To answer your question: I guess my answer is predicated on the fact that I live in mine 24/7 and only have a 50 gal combined black/gray. It's what you called a post bus. Minimal tankage for a few days on the road, and is tied to a "post" most of the time. Probably shoulda' kept my keyboard "off" on this one. See 'ya in Arcadia! ...JJ | ||
| two dogs (66.90.210.43) Rating: N/A |
o.k. you win....I tore it all out....no more two dogs vent.....I don't believe in r.v. toilets...seems silly to spend 10 times as much on something that doesn't work without working & spraying silicone spray...I like my FERGUSON...(china toilet) I'm going to vent to the wheelwell | ||
| Marc Bourget (209.142.38.81) Rating: N/A |
Dear two dogs, (Pun inended) Are you saying that this will work for you and nobody will be able to tell the difference between your vents and from you "marking" your tires? Personally, I don't have any experience with the wheel well vents but the roof hole doesn't threaten me that much and I'll go with it. To complete the thought, a strong roof top viewing stand, like on the Wanderlodges, will conceal and protect the vents in any case. Onward and Upward Marc Bourget | ||
| Don KS/TX (65.141.166.20)
Rating: N/A |
Now THAT is disgusting Marc, sitting on top of the bus with the poop vent coming up between your legs? Wheel well vents for me! | ||
| Casual_Observer (207.109.1.73) Rating: N/A |
Done properly, the poop vent works well to hold your can of beer. Picture this... Two Dogs marking tires FROM the roof top viewing stand. Now that's disgusting! | ||
| Don KS/TX (65.149.4.173)
Rating: N/A |
Someone else suggested lighting the methane vapors, to form a type of mosquito control for the rooftop sitters. | ||
| Scott Whitney (66.82.9.20) Rating: N/A |
Not only works as a beer holder, but from your rooftop party platform, when you are done with your beer, you can prolong the ladder climb down and just whiz down the vent. Scott | ||
| Don KS/TX (65.150.144.194)
Rating: N/A |
Hey Scott, I had not thought of THAT either!! Maybe roof vents are the best way to go afterall!! | ||
| two dogs (66.90.213.12) Rating: N/A |
no need to whizz down the vent,plenty of fords driveing by......... | ||
| the phantom whizzer.... (170.215.36.143) Rating: N/A |
Yep, Whizz in a stream or a fjord or ford that stream, it's all in how you want to relieve yourself....... | ||
| pete (152.163.252.163)
Rating: N/A |
it blows my mind that only a very few of you who have written have general plumbing in mind.. take it straight up threw the roof..1 1/2 pipe is perfect no less...no more..the rv store has the cap for you.. altitude, heat even the hi and lo preasure of the air will make the black water tank expand and contract..so..get it out of nose shot wheel well not smelling? done right or wrong..if your anywhere near it..your going to get a snoot full not to mention a new ass from the guy who has to change the tire. dont forget the common sence element here..tho..as usual..the comics have had awsome responces pete | ||
| doneda (65.141.167.26)
Rating: N/A |
The point was Pete, that General Plumbing (I can't recall just which war he fought in) is not necessarily the ONLY guy that knows how to do it right. I used and have seen others use the wheel well method, and nobody ever once got a snoot full of anything. One friends response was always "Just go back there and sniff, and YOU tell me which wheel well has the vent". What you use in the black tank to tame it down can sure make a difference too, and in my case I combined the black and grey, probably made it less explosive in nature too. I suppose every 5 years or so when you changed a tire, you could just cork it. Many appreciate not having more holes in the roof to chance a leak, and knowing that it still may stink inside because air currents flowing over the bus when in motion may pressurize the system. | ||
| two dogs (66.90.210.171) Rating: N/A |
I ain't changin' it again, the wheelwell forever.just hope the guy changin' the tire doesn't use ether..saw them do it many times on bigtrucks....ya' ever seen a tire changed & they leave the wheel on the truck ? fast!! I'm really not that afraid of methane..I think propane is 100 times more dangerous | ||
| pete (205.188.208.39)
Rating: N/A |
you can at least smell propane | ||
| Don KS/TX (65.141.166.194)
Rating: N/A |
Actually you CANNOT smell propane! They have to add a perfume so that you can tell where it is and you are only smelling the perfume. Now for the trivia question of the day: What is the name of the perfume added to propane that you actually smell? Any guesses? | ||
| Jack Conrad (Jackconrad) (207.30.189.58)
Rating: N/A |
Mercaptin (sp?) Jack | ||
| Don KS/TX (65.141.167.102)
Rating: N/A |
Darn, you learn some worthless piece of information just to feel smart, and someone else memorizes it too. Mercaptan seems to be the correct spelling, but you would look silly sniffing around saying "I think I smell a mercaptan leak? now wouldn't you. | ||
| two dogs (66.90.222.234) Rating: N/A |
mer-captan....yep....he took orders from that general plumbing...it's all becoming clear now | ||
| Don KS/TX (65.150.145.237)
Rating: N/A |
Ian probably wishes we would go someplace else and play by now. | ||
| Dale MC8 (66.81.138.60)
Rating: N/A |
ethel mercaptin (sp?) Dale | ||
| Peter Broadribb (Madbrit) (65.73.112.211)
Rating: N/A |
Yep, knew her sister Mabel, nice girl she was, a pleasure to be with, not like her sister Ethel, who had rather a strong odor....... | ||
| two dogs (66.90.216.191) Rating: N/A |
YEAH,,,,,,BUT SHE SURE COULD SING | ||
| Peter Broadribb (Madbrit) (65.37.90.28)
Rating: N/A |
But she Hummmmmmed better........ | ||
| two dogs (66.90.216.192) Rating: N/A |
YEP............SHE WAS A DARLIN |